Indicator: Air Temperature Change in the Chesapeake Bay Watershed (1901 - 2021)

<p><strong>Access the Indicator Materials:</strong><br />- <a target="_blank" href="https://d18lev1ok5leia.cloudfront.net/chesapeakeprogress/chart-assets/average-air-temperature-increases-in-the-chesapeake-bay-watershed-1901-2017/Analysis-and-Methods_2021_Average-Air-Temperature_072523_final.docx">Analysis &amp; Methods</a><br />- <a target="_blank" href="https://d18lev1ok5leia.cloudfront.net/chesapeakeprogress/chart-assets/average-air-temperature-increases-in-the-chesapeake-bay-watershed-1901-2017/Data_2021_Climate-Indicators_4.27.2023-1.xlsx">Data File</a><br />- <a target="_blank" href="https://gis.chesapeakebay.net/ags/rest/services/ChesapeakeProgress/cpClimate_Avg_Temp/MapServer">Map Service</a></p><p>This metric is based on temperature data collected from land-based weather stations and compiled in NOAA’s nClimDiv dataset, which is maintained by the National Centers for Environmental Information. The nClimDiv analysis averages climate data across U.S. climate divisions, and temperature trends are calculated by regressing annual climate division anomalies and converting the slope to a rate of change per century.</p><p><strong>Note: This Indicator supported progress tracking toward the Monitoring and Assessment Outcome in the original Chesapeake Bay Watershed Agreement, adopted in 2014. The Watershed Agreement and Adapting to Changing Environmental Conditions Outcome were revised in 2025.</strong></p>